BRUES: PARASITIC HYMENOPTERA. 7 



the occurrence of Leptobatopsis and Ormyrodes respectively, but 

 these may have no general significance, and I do not believe that they 

 have. The abundance of Ophioninae and Pimplinae, particularly 

 of the former, would appear to be expressions of Neotropical tenden-. 

 cies, and I think they may quite probably be so. 



The exact relationships of the present fauna of the United States 

 and of that of Florissant during Miocene times can be traced in the 

 accompanying table. The number of fossil species are contrasted 

 with the number of recent species occurring in the United States 

 (according to Cresson, 1888) and the third column of figures gives the 

 proportionate number of species in the two faunae. 



The designation of the special localities for certain of the species 

 collected by Professor Cockerell's expeditions is in accordance with 

 his numbers of stations as given in one of his recent papers (:07). 

 The specimens in the Scudder collection have no indication of which 

 specific localities or beds they w T ere taken from, except that all were 

 taken from the Florissant lake basin. 



I wish to gratefully acknowledge the courtesy of the authorities of 

 the Museum of Comparative Zoology for the loan of the Scudder 

 collection and the assistance given by Professor Cockerell who first 

 suggested to me the great interest attaching to the Florissant fauna, 

 and who aided by the sending of much material. I am indebted to 

 Dr. H. C. Bumpus and Mr. R. W. Miner of the American Museum 



